Misc: What did to decimate originally mean in military terms?

Questions

The largest muscle in the human body is the?

The Islands of Langerhans won't be found on a map, they're a group of cells located in the?

Every time you step forward, you use ________ muscles?

A Rhinologist specialises in the human?

If you could remove all the space from the atoms that make up your body, you could walk through the?